I had a chance to test the Toycen Tradesman Grinder, a variable speed grinder with a DC motor that delivers a lot of torque even at the lowest speeds. It’s rated at 400 – 4000 rpm and claims five foot-pounds of torque at 1000 rpm. I loaded it up at low speed, pushing a piece of steel against the wheel with more force than I would ever use with a bonded-abrasive wheel and I could barely slow it down at all. The wheels — the ones I tested — are coated with cubic boron-nitride (CBN) for grinding steel. CBN is preferred over diamond for grinding steel if there is a chance the grinding process will generate red-heat temperatures. At high temperatures the diamond can be absorbed into the steel. Yes, steel loves carbon that much. So with CBN you can grind to your heart’s content (even carbide!) And the variable speed goes a long way to control that heat, allowing for relatively cool grinding of hardened steel. According to Toycen, as much as 50% of a grinder’s power is spent breaking down the stone wheel, generating heat and dust. With a bonded CBN wheel, no power is lost to stone wear and the only dust generated is the steel removed from whatever you are grinding.
The wheels are heavy (8 pounds each, 100 and 180-grit standard on this model) and precisely balanced. The Toycen video above demonstrates the smooth running by balancing a “loonie” on top (they’re a Canadian company, eh) through the full speed range. We use belt grinders here at the Hock shop, partly because I don’t like bench grinders all that much. Oh, they do they’re job and are almost essential for some things — and certainly handy for so many more — but bench grinders are rarely balanced, need constant dressing and truing and make way too much gritty dust. But the Toycen’s power, balance and quiet-running make this bench grinder a real pleasure to use.
The Tradesman I tested included a rod fixture that allows the use of all the Tormek jigs adding immensely to the functionality of this grinder. And there are other options — wheel sizes, a belt grinder attachment — to serve many needs. The model I tested lists at $1275, a price that may discourage many woodworkers. But when you compare that with an 8-inch Baldor at $1029, and compare the Toycen’s considerable advantages, its price doesn’t seem so out of line.
For more about diamond, CBN and other abrasives, along with much more about tool steel and sharpening in general, read my book, The Perfect Edge.